Eating seafood and cognitive decline in older adults.

WHAT WAS THIS STUDY ABOUT? In the article “APOE e4 and the associations of seafood and longchain omega-3 fatty acids with cognitive decline,” van de Rest and colleagues examined the connection between the amount of seafood eaten per week and cognitive decline over approximately 5 years in older adults living in retirement communities. The researchers were also interested in learning more about how a gene called APOE e4 might influence the effect that seafood consumption has on cognitive decline. The community-based study was designed to better understand changes in thinking and motor abilities and the risk of Alzheimer disease (AD) in older adults. The study was called the Rush Memory and Aging Project or MAP. In 2015, 46.8 million people worldwide had dementia, and this number is expected to double every 20 years. AD is the most common type of dementia. There is currently no proven therapy that can prevent or cure AD, so it is important to understand and identify factors that might prevent or delay the onset of AD and other dementias. Researchers are interested in the fats contained in fish and seafood. These fats are called omega-3 fatty acids. These fats are of interest to researchers because the brain contains a high amount of omega-3 fatty acids. It is also known that these fatty acids are needed for a healthy brain. With aging, these fatty acids may decrease, so keeping healthy levels of them in the brain may prevent or delay cognitive decline. The APOE e4 gene is involved in moving cholesterol to cells, including brain cells. This gene may also have an effect on how omega-3 fatty acids are moved into brain cells. People who have the APOE e4 gene have an increased risk of AD. Those over age 65 are at the highest risk for AD.